Envelope stuffing machine

ABSTRACT

An envelope stuffing machine includes a pair of pivot arms swingable from a rest position to an operative position and back to the rest position during each cycle of operation. Each of the arms is provided at one end with a hook-shaped member adapted to move into the mouth of an envelope positioned at a filling or stuffing station of the machine for opening and maintaining open the mouth of the envelope during a stuffing operation. The pivot arms are eccentrically supported such that as they swing, from the rest position to the operative position and back to the rest position, the hook-shaped members travel on a generally circular path. Thus the hook-shaped members enter the mouth of the envelope on a first path and maintain the mouth open during the stuffing operation, and are withdrawn from the mouth of the envelope on a second path so as to avoid partial withdrawal of the stuffed material from the envelope.

United States Patent 1 Dorer 1 June 3,1975

[ ENVELOPE STUFFING MACHINE [75] Inventor: Wilfried Dorer, Robberg, Germany [73] Assignee: Addressograph-Multigraph Corporation, Cleveland, Ohio 22 Filed: Feb. 14,1974

211 Appl. No.: 442,470

Primary ExaminerTravis S. McGehee Attorney, Agent, or Firm-Sol L. Goldstein [57] ABSTRACT An envelope stuffing machine includes a pair of pivot arms swingable from a rest position to an operative position and back to the rest position during each cycle of operation. Each of the arms is provided at one end with a hook-shaped member adapted to move into the mouth of an envelope positioned at a filling or stuffing station of the machine for opening and maintaining open the mouth of the envelope during a stuffing operation. The pivot arms are eccentrically supported such that as they swing, from the rest position to the operative position and back to the rest position, the hook-shaped members travel on a generally circular path. Thus the hook-shaped members enter the mouth of the envelope on a first path and maintain the mouth open during the stuffing operation, and are withdrawn from the mouth of the envelope on a second path so as to avoid partial withdrawal of the stuffed material from the envelope.

7 Claims, 3 Drawing Figures PATENTEU JUF! 3 I975 SHEET 1 ENVELOPE STUFFING MACHINE BACKGROUND OF THE INVENTION In a known prior art device there is provided a pair of swinging arms each provided at one end with a wedge-shaped spreading finger. The swinging arms are supported on a common, cam-controlled shaft positioned a fixed distance above the filling station at which the mouth of the envelope comes to rest while it is being stuffed. The spreading fingers are so arranged on the swinging arms that, as the swinging arms are moved from a rest position to a position wherein the wedgeshaped spreading fingers enter the mouth of the envelope, the fingers engage the front and rear walls of the envelope and spread them apart. Additionally, however, such prior art devices also require that a blast of air be introduced into the mouth of the envelope in order to open the mouth sufficiently wide so that the filling material can be inserted therein. With this arrangement it is necessary to time the blast of air so that the air blast is provided just prior to the arrival of the spreading fingers at the mouth of the envelope such that the spreading fingers may enter between the front and the rear walls of the envelope.

Aside from the additional mechanism required by the prior art device for providing a blast of air and a timing control therefor, which adds considerably to the cost of the device, the spreading fingers of the prior art device are arranged to move into and out of the mouth of the envelope on a common path. Normally, because the spreading fingers can only insert the filling material into the envelope to a point such that the rear edge of the filling material still lies outside of the spreading fingers, and because the position in which the spreading fingers hold the mouth of the envelope open places the spreading fingers against the inside of the front wall of the envelope, the rearward movement of the spreading fingers traveling on the same path as the forward movement of the fingers frequently results in partial withdrawal of the filling material from the envelope.

SUMMARY OF THE INVENTION The present invention provides a device for opening and maintaining open the mouth of an envelope utilizing a pair of pivot arms each provided at its end with a hook-shaped member or finger for entering the mouth of the envelope. The pivot arms are eccentrically supported such that as they are swung or pivoted from a rest position to an operative position wherein the fingers enter the mouth of the envelope and return to the rest position, the fingers of the pivot arms are caused to travel on a generally circular path. In this way the fingers are effective to open the mouth of the envelope, maintain the mouth open during stuffing of the envelope and are withdrawn from the envelope without disturbing the contents therein.

The objects and advantages achieved by the present invention result from the use of pivot arms providing hook-shaped fingers arranged at the lower ends of the pivot arms. The pivot arms are free to move in a generally vertical direction and otherwise vertically adjustable at their upper ends and are supported for pivotable movement on a stationary shaft. The arms are connected at a point below the stationary shaft with a com mon eccentric shaft which is intermittently driven by means of a cam control. The eccentric arrangement, which provides circular motion to the fingers of the pivot arms, provides for opening and holding open the mouth of the envelope, i.e., the spreading apart of the front and back walls of the envelope. This action is effected mechanically by the fingers without the aid of an air blast as in prior art devices and provides uniform opening of the envelope.

The fingers in their rearward movement from the mouth of the envelope do not travel on the same path on which they entered the mouth of the envelope and, therefore, do not disturb the contents within the envelope. Rather, the fingers in their rearward movement from the mouth of the envelope travel in a plane in which they have held the mouth of the envelope open. This plane, however, according to the eccentricity of the eccentric shaft and the lever conversion selected, may be placed sufficiently above the plane of the filling of the envelope such that the fingers do not contact the filling material stuffed into the envelope.

Preferably, the circular movement of the fingers is divided into two sections, a first movement section which includes an angle of movement of about 270 beginning with a downward movement and ending with an upward movement, and a second section of movement including about in which the remaining circular motion is described from the spread position of themouth of the envelope to the rest position of the pivot arms.

The eccentric shaft is formed in the manner of a crank having formed ends guided in elongated holes provided in guide pieces secured on the pivot arms. Aside from providing a simple manufacturing and mounting arrangement, the eccentric mounting also permits the fingers to lie freely by their own weight on the inside of the front wall of the envelope thereby assuring a better grip under the back wall of the envelope when the fingers are introduced into the mouth of the envelope.

The cam control means for intermitently driving the eccentric shaft is. provided with a pair of cam discs fixed thereon and driven in unison through a friction coupling. Each of the cam discs is provided with a stop member, the stop-members being displaced from each other by about 270. In the rotary paths of movement of the cam discs, the stop members alternately engage a pair of stop projections provided on a machine control lever and displaced from each other by about 180. This arrangement provides an accurate and positive control of the pivot arms and the fingers, both timewise and in phase, in a simple manner.

Preferably, during the first phase the machinecontrolled swinging lever is driven by a solenoid controlled by a first end switch arranged at the filling station of the envelope stuffing machine, and by means of a second machine-controlled switch during the second phase of movement,

It is an object of the present invention to provide a simplified device for opening and maintaining open the mouth of an envelope during an envelope stuffing operation without the assist of an air blast as required in prior art devices.

Another object of the invention is to provide a pair of pivot arms having hook-shaped fingers swingable from a rest position to a position within the mouth of the envelope and back to the rest position. The pivot arms are eccentrically supported such that in their swinging motion the eccentric means causes the fingers to move on a circular path thereby entering the mouth of the envelope on a first path, holding the mouth of the envelope open during an envelope stuffing operation, and withdrawing from the mouth of the envelope on a separate path so as not to disturb the contents in the envelope.

Another object of the present invention is attained by the pivot arms being equipped with lifting fingers for lifting a pressing weight supported on a swinging lever, the weight normally resting on the envelope during the opening and the holding open of the mouth of the envelope. Such pressing weights are necessary, when the table of the filling station is equipped with one or more conveyor belts, to signal the correct end position of an oncomming envelope, for example, as the envelope is carried further towards an electric switch and/or towards the filling station.

Other objects, features and advantages of the invention will appear hereinafter as the discription proceeds.

In the drawing:

FIG. 1 is a front elevation of an envelope filling station of the envelope-stuffing machine according to the present invention;

FIG. 2 is an end elevation, partially in section, showing an eccentric means for mounting a pair of pivot arms earring hook-shaped fingers together with a cam control means for driving the eccentric means; and

FIG. 3 is a front elevation of the cam control means for driving the eccentric means.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to FIG. 1, there is shown a filling station of an envelope-stuffing machine comprising a table 1 equipped with conveyor belts 4, carried by rollers 2 and 3, with the upper stretch of the belts being supported by a plate 5. The table 1 is provided at one end with a stop 6 and an electric end switch 7. A plurality of metal or glass balls 8 are each loosely guided in a corresponding lever 9 and rest on the upper stretches of the conveyor belts 4. The levers 9 are fastened so as to swing on a bearing stand 10 through pivots 11 and, as will be further explained hereinafter, are adapted to be raised upwardly away from the conveyor belts 4. For this purpose each of the levers 9 is provided at its front end with an angled tongue 12.

With further reference to FIG. 1, envelopes 13 to be filled or stuffed are fed in the direction of arrow 14 by means of conveyor belts 15 which are arranged in the same plane as the conveyor belts 4 and 5.

A flap 16 of the envelope 13 is turned up or opened prior to the envelope 13 arriving at the table 1. During the filling or stuffing process of .the envelope, the flap 16 lies between two conveyor rolls 17 and 18 which are arranged between the conveyor belts 4, 5 and 15. Subsequent to the opening of a mouth 19 of the envelope 13, the filling to be stuffed into the envelope is introduced into the mouth of the envelope by means of diagonally positioned conveyor belts 20 and 21 in the direction of arrow 22 shown in FIG. 1. The conveyor belts 20 and 21, for example, receive material to be stuffed into the envelopes from a folding machine.

Above the position at which the mouth 19 of the envelope l3 normally comes to rest, there is arranged at a fixed distance from each other (see FIG. 2) a pair of substantially vertical pivot arms 23, (see FIG. 1). The lower ends of the pivot arms 23 are angled and designed as hook-formed, sharp-edged spreading fingers 24. The upper ends of the pivot arms 23 are movably or slidably secured to bearing blocks 27, by screws 26, and are adapted for free vertical sliding moyement by means of elongated holes 25 provided in the pivot arms. The bearing blocks 27 are rotatably supported on a stationary shaft 28 and the shaft 28 is supported in a pair of side plates 29 and 30. v

Positioned directly below the shaft 28 and parallel therewith there is provided an eccentric shaft or bell crank 31 rotatably supported in the side plates 29 and 30. A formed eccentric portion 32 of the eccentric shaft 31 projects through a pair of guide blocks 33 (see FIG. 2) each of which is provided with an elongated opening 34. The guide blocks 33 are secured to the pivot arms 23. Adjacent the outer face of the side plate 29, on an extended portion 35 of the eccentric shaft 31, there is provided a gear 36 positioned between a stationary ring 37 and a bushing 38. The stationary ring 37 and the bushing 38 are held against rotation on the shaft 35 but are movable axially thereon. The bushing 38 is urged against the gear 36 by a compression spring 39 such that there is provided a friction coupling between the bushing 38 and the gear 36 and, also, between the eccentric shaft 31 and the gear 36.

The gear 36 is in mesh with a continuously rotating driving gear 40. As shown in FIGS. 2 and 3, a pair of non-rotatable cam discs 41 and 42 are secured on the bushing 38 in spaced apart relationship. Each of the discs 41 and 42 is provided with a stop cam 43 and 44 respectively, positioned at an angular distance of about 270 from'each other. The stop cams 43 and 44 cooperate alternately with a pair of stop projections 45 and 46 respectively, positioned on correspondingly formed forked arms 47 and 48 of a swinging lever 49 respectively, at an angular distance of about from each other. The stop projections 45 and 46 are integral with the swinging lever 49 which is supported so that it can swing on a stub shaft 50 which also serves as a support for the gear 40. A tension spring 51 connected to the lever 49 acts against the attraction force of a solenoid 52. The solenoid 52 is provided with a plunger 53 connected to an arm 54 of the swinging lever 49 at a position opposite the end of the swinging lever 49 provided I with the forked arms 47 and 48. When the solenoid 52 is de-energized the stop projection 45 of the forked arm 47 engages with the stop cam 43 as shown in FIG. 3. When the solenoid 52 is energized, in response to actuaction of the end switch 7 by the envelope 13 arriving at its end position on the table 1, the swinging lever 49 is caused to rotate through a first movement in which the stop cam 43 is released and the stop projection 46 is caused to move into engagement with the stop cam 44. During this movement the eccentric shaft 31 is rotated through an angular movement of about 270.

When the solenoid 52 is, again de-energized, the spring 51 urges the swinging lever 49 to a starting position shown in FIG. 3, and the stop projection 46 is out of engagement with the stop cam 44. Thus, the eccentric shaft 31 during the second part of the movement rotates through the'remainder of a full revolution until such time as the stop cam 43 again abuts the stop projection '45;

During these two movements of the eccentric shaft 31, the fingers 24 of the pivot arms 23 are alternately moved through a circular path. The movement of the fingers 24 is shown in FIG. 1 wherein the finger 24 is first lowered from a home position shown in dotted lines by the reference character I on a first circularpath to the full line position on the inside of the lower wall of the envelope 13, i.e., on the inside of the front wall of the envelope 13. During further movement the finger 24 is guided through a second path under the rear edge of the back wall of the envelope l3 and then raised with the rear wall of the envelope into the dotted line position shown by the reference character 11. In the position II, the stop cam 44 abuts the stop projection 46 of the swinging lever 49. This condition is maintained until the material to be stuffed into the envelope is completely inserted into the envelope 13.

With reference to FIG. 1, it will be seen that during the foregoining operation the mouth 19 of the envelope 13 is held open by the fingers 24. After the filling material has been stuffed into the envelope 13, the solenoid 52 is de-energized by a machine-controlled switch, not shown in the drawings. Thereafter, and as described above, the second phase of movement of the eccentric shaft 31 causes the fingers 24 to move through the second path from the position II to the position I. During this movement of the finger 24 through the second path, the finger 24 travels on a circular path which first raises from the position II to the position I such that the fingers 24 are moved away from the back wall of the envelope 13 without disturbing the contents within the envelope 13.

For raising the balls 8 from the envelope 13, the pivot arms 23 are each provided with a lifting finger 55 which engages the tongue 12 of a corresponding lever 9 and lifts the ball 8 until the fingers 24 are returned from the position II to the position 1.

Although the foregoing embodiment describes an arrangement for stuffing the envelopes 13 lying in a horizontal plane on the table 1, it is to be understood that the device of the present invention can also be arranged for stuffing envelopes positioned in a diagonal plane.

What is claimed is:

1. Apparatus for opening and holding open the mouth of an envelope at a filling station of an envelope stuffing machine, comprising:

an envelope feed path for feeding said envelope along a predetermined plane to said filling station;

a pair of pivotable arms disposed in a generally normal direction to said envelope feed path, said arms being equipped with a hook-shaped spreading member;

means for supporting said arms in spaced apart parallel relation on first and second support means extending transversely of said arms, said first support means defining a pivoting axis for said arms;

support mounting means on said first and second support means permitting displacement of the arms in a vertical direction relative to said predetermined plane; and

drive means for intermittently imparting rotary motion to said second support means causing said spreading members to move on a generally circular path from a rest position clear of the mouth of the envelope and into an operative position holding open the mouth of said envelope and returning to said rest position after said envelope had been stuffed.

2. The apparatus as set forth in claim 1 in which said second support means comprises a bell crank mechanically coupled to said drive means comprising a solenoid 6 actuated ear means 'forimparting to said second suppmmeans-g 3;An apparatus as'iset' forth' in claim lwh'ich further includeswfeight means forar'i-estirig' andf holding an en- 5 ve1P? 't the-filling -station when the spreading members are in the rest position; and

means associated with the pivotable arms for lifting the weight means from the envelope in response to movement of the spreading members from the rest of the operative position.

4. An apparatus as set forth in claim 2 in which the drive means comprises:

a pair of cams discs secured on one end of the bell crank;

a stop cam provided on each of the cam discs positioned in angularly displaced relationship with each other;

means for driving the cam discs inounison; and

a machine controlled swinging lever provided with a pair of angularly displaced stop projections each positioned in the path of movement of one of the cam discs for alternate engagement of the stop projections with the stop cams of the cam discs.

5. Apparatus for opening and holding open the mouth of an envelope at a filling station of an envelope stuffing machine, comprising:

a pair of dependent pivotable arms each provided with a hook-shaped spreading member, said pivotable arms being swingable to move the spreading members from a rest position spaced from the envelope to an operative position for spreading and holding open the mouth of the envelope and return back to the rest position;

means for supporting the pivotable arms for pivotal and vertical movement in parallel spaced apart relationship on first and second support means extending transversely of the arms, said first support means defining a pivoting axis for the arms;

support mounting means on the first and the second support means permitting displacement of the arms in a vertical direction relative to an envelope feed path along a predetermined plane; and

drive means including bell crank means for moving the spreading members on a generally circular path including a first path from the rest position to the operative position and on a second path from the operative position back to the rest position.

6. An apparatus as set forth in claim 5 which further includes control means for intermittently driving the drive means and moving the spreading members into and out of the mouth of the envelope.

7. Apparatus for opening and holding open the mouth on an envelope at a filling station of an envelope stuffing machine, comprising:

said rotary motion hook-shaped spreading member, said pivotable arms being swingable to move the spreading members from a rest position spaced from the envelope to an operative position for spreading and holding end with a formed portion for moving the spreading members on a generally circular path including a first path from the rest position to the operative a pair of pivotable pivot arms each provided with a v7 8 position and on a second path from the; operative ally circular motion to the spreading members; and position back to therest position; 4 control means for intermittently driving the drive guide means provided on the pivotztb le arms for remeans and moving the spreading members into and ceiving astraightsection of the hell crunk intermeout of the mouth of the envelope.

diate the formed end portions for imparting g cner- 

1. Apparatus for opening and holding open the mouth of an envelope at a filling station of an envelope stuffing machine, comprising: an envelope feed path for feeding said envelope along a predetermined plane to said filling station; a pair of pivotable arms disposed in a generally normal direction to said envelope feed path, said arms being equipped with a hook-shaped spreading member; means for supporting said arms in spaced apart parallel relation on first and second support means extending transversely of said arms, said first support means defining a pivoting axis for said arms; support mounting means on said first and second support means permitting displacement of the arms in a vertical direction relative to said predetermined plane; and drive means for intermittently imparting rotary motion to said second support means causing said spreading members to move on a generally circular path from a rest position clear of the mouth of the envelope and into an operative position holding open the mouth of said envelope and returning to said rest position after said envelope had been stuffed.
 1. Apparatus for opening and holding open the mouth of an envelope at a filling station of an envelope stuffing machine, comprising: an envelope feed path for feeding said envelope along a predetermined plane to said filling station; a pair of pivotable arms disposed in a generally normal direction to said envelope feed path, said arms being equipped with a hook-shaped spreading member; means for supporting said arms in spaced apart parallel relation on first and second support means extending transversely of said arms, said first support means defining a pivoting axis for said arms; support mounting means on said first and second support means permitting displacement of the arms in a vertical direction relative to said predetermined plane; and drive means for intermittently imparting rotary motion to said second support means causing said spreading members to move on a generally circular path from a rest position clear of the mouth of the envelope and into an operative position holding open the mouth of said envelope and returning to said rest position after said envelope had been stuffed.
 2. The apparatus as set forth in claim 1 in which said second support means comprises a bell crank mechanically coupled to said drive means comprising a solenoid actuated gear means for imparting said rotary motion to said second support means.
 3. An apparatus as set forth in claim 1 which further includes weight means for arresting and holding an envelope at the filling station when the spreading members are in the rest position; and means associated with the pivotable arms for lifting the weight means from the envelope in response to movement of the spreading members from the rest of the operative position.
 4. An apparatus as set forth in claim 2 in which the drive means comprises: a pair of cams discs secured on one end of the bell crank; a stop cam provided on each of the cam discs positioned in angularly displaced relationship with each other; means for driving the cam discs in unison; and a machine controlled swinging lever provided with a pair of angularly displaced stop projections each positioned in the path of movement of one of the cam discs for alternate engagement of the stop projections with the stop cams of the cam discs.
 5. Apparatus for opening and holding open the mouth of an envelope at a filling station of an envelope stuffing machine, comprising: a pair of dependent pivotable arms each provided with a hook-shaped spreading member, said pivotable arms being swingable to move the spreading members from a rest position spaced from the envelope to an operative position for spreading and holding open the mouth of the envelope and return back to the rest position; means for supporting the pivotable arms for pivotal and vertical movemEnt in parallel spaced apart relationship on first and second support means extending transversely of the arms, said first support means defining a pivoting axis for the arms; support mounting means on the first and the second support means permitting displacement of the arms in a vertical direction relative to an envelope feed path along a predetermined plane; and drive means including bell crank means for moving the spreading members on a generally circular path including a first path from the rest position to the operative position and on a second path from the operative position back to the rest position.
 6. An apparatus as set forth in claim 5 which further includes control means for intermittently driving the drive means and moving the spreading members into and out of the mouth of the envelope. 